7.3.1以10为底的浮点指数函数.txt

51单片机实用子程序

FE10: 
MOV 	R5,#2 				
MOV 	R6,#0D4H
MOV 	R7,#9AH
;先进行加权运算，后以2为底统一求幂
CLR 	1EH 				
MOV	A,@R0				
MOV	C,ACC.7
MOV	1FH,C
MOV	C,ACC.6
MOV	ACC.7,C
MOV	R2,A
INC		R0
MOV	A,@R0
MOV	R3,A
INC		R0
MOV	A,@R0
MOV	R4,A
DEC		R0
DEC		R0
LCALL 	MUL1 				
E20: 
MOV 	A,R3
ORL 	A,R4
JZ 		EXP1 				
MOV 	A,R2
JB 		ACC.7,EXP2			
SETB 	C
SUBB 	A,#6 				
JC 		EXP2
JB 		1FH,EXP0				
MOV 	@R0,#3FH				
INC 		R0
MOV 	@R0,#0FFH
INC 		R0
MOV 	@R0,#0FFH
DEC 	R0
DEC 	R0
SETB 	OV
RET
EXP0: 
MOV 	@R0,#41H				
CLR 	A
INC 		R0
MOV 	@R0,A
INC 		R0
MOV 	@R0,A
DEC 	R0
DEC 	R0
CLR 	OV
RET 
EXP1: 
MOV 	@R0,#1 				
INC 		R0
MOV 	@R0,#80H
INC 		R0
MOV 	@R0,#0
DEC 	R0
DEC 	R0
CLR 	OV
RET 
EXP2: 
MOV 	A,R2 			
MOV 	R5,A
MOV 	A,R3
MOV 	R6,A
MOV 	A,R4
MOV 	R7,A
MOV 	C,1FH
MOV 	1EH,C
;对第一区取整
INT:	
MOV	A,R3					
ORL		A,R4
JNZ		INTA
CLR		1FH
MOV	R2,#41H
RET
INTA:	
MOV	A,R2
JZ		INTB				
JB		ACC.7,INTB			
CLR		C
SUBB	A,#10H				
JC		INTD
RET							
INTB:	
CLR	A	  					
MOV	R4,A
MOV	C,1FH
RRC	A
MOV	R3,A
RL	A
MOV	R2,A
JNZ	INTC
MOV	R2,#41H 
INTC:	
RET
INTD:	
CLR		F0
MOV 	A,R3
JZ 		EXP4
EXP3: 
CLR 	C 					
RRC 	A
INC 		R2
CJNE 	R2,#8,EXP3
EXP4: 
MOV 	R3,A
JNB 		1FH,EXP5
CPL 		A 				
INC 		A
EXP5: 
PUSH 	ACC 				
RLNORM:	
MOV	A,R3					
ORL		A,R4				
JNZ		RLNORM1
MOV	R2,#0C1H				
RET     	
RLNORM1:	
MOV	A,R3
JB		ACC.7,RLNORM2		
CLR		C					
LCALL	RL1
SJMP	RLNORM				
RLNORM2:	
CLR		OV					
RET
RL1:	
MOV	A,R4				
RLC		A					
MOV	R4,A
MOV	A,R3
RLC		A
MOV	R3,A
DEC		R2					
CJNE	R2,#0C0H,RL1E			
CLR		A
MOV	R3,A					
MOV	R4,A
MOV	R2,#0C1H
RL1E:	
CLR		OV 
CPL		1FH
SETB	F0
RET